Turner, 26, drove in 20 runs while also batting .325 (27-for-83) with a homer for the month. He added eight doubles, nine runs and two stolen bases while notching a .378 on-base percentage and .458 slugging percentage.
"It means I was good this month," Turner said. "It will be something really cool to look back on down the road, but now I've just got to show up tomorrow and get ready for tomorrow. There's no time to pat myself on the back."
The seventh-round pick in the 2006 First-Year Player Draft by the Reds out of Cal-State Fullerton is batting .320 with two home runs, 22 RBIs and 11 runs this season for New York.
Turner set a Mets rookie record with an RBI in seven consecutive contests (12 RBIs total) from May 14-21. According to the Elias Sports Bureau, his 13 RBIs over a 15-game span from May 14-30 makes him just the third big league rookie to do so, and first since 1930.
He also recorded a career-best eight-game hitting streak from May 13-21, during which he tallied three consecutive multihit games.
It is Turner's first weekly award, and he becomes the first Met to win NL Rookie of the Month honors since the award's inception in 2001.